SOUND_MIXER_PCM
#define SOUND_MASK_PCM (1 << SOUND_MIXER_PCM)
#define SOUND_MIXER_READ_PCM MIXER_READ(SOUND_MIXER_PCM)
#define SOUND_MIXER_WRITE_PCM MIXER_WRITE(SOUND_MIXER_PCM)
{ SOUND_MIXER_PCM, "PCM", 0 },